A Novel Offshore Acoustic Sensing Array: Unifying Clock Source to Every Hydrophones Acquisition Node

摘要

A high-precision clock source (±2.0 ppm) in the head of array was used to generate unified acquisition and transmission clock, each hydro-acoustic acquisition node recovered local standard clock from the unified source via PLLs. The real-time transmission path of clock and data was pipelined, which is based on RS-485 and positive emitter coupled logic (PECL). Synchronous serial data communicated at 196.608 Mbps by non-shielded twisted-pair (Cat 6) in the length of 100 meters, which can guarantee a strong anti-jamming capability and good real-time features. Clock transmission and data acquisition experiments were carried out in the Lab, and results show that the hydrophones array can be a good system for real-time undersea acoustic exploration.